On Thu May 03 18, Laurent Bigonville wrote:
Le 15/03/18 à 17:24, Jarkko Sakkinen a écrit :
On Fri, 2018-03-09 at 18:24 +0100, Laurent Bigonville wrote:
The duration that that was in your patch seems to work, cannot this be
implemented?
I'm quite surprised I'm the only one impacted by this...
Sorry it took so long time response but I had forgotten so too many
details.
After re-reading (PHEW!) the whole thread I'm thinking if we could
use section 5.5.2.4 as a reference to select a timeout of TIMEOUT_A
(albeit it is for request locality) and use Jerry's suggestion to
put wait_for_tpm_stat() there? Opinions?
Hey,
Sorry to bother you again, but are there any progress on getting this
mainlined?
Kind regards,
Laurent Bigonville
Jarkko would something like this work? Building it to test on tpm2.0 system right now.
I don't have access to a system with a tpm1.2 tis device at the moment. I tested a
patch similar to this based on the slightly older code that is currently in the
rhel kernel and it seemed work fine. release_locality was still a void function
back then, so might have to think more about the return values here and checking
them. Also wondering if release_locality, check_locality, and wait_for_tpm_stat
can be refactored since they would all have basically the same chunk of code.
Jerry
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 5a1f47b43947..31ee154450eb 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -143,12 +143,56 @@ static bool check_locality(struct tpm_chip *chip, int l)
return false;
}
+static bool locality_inactive(struct tpm_chip *chip, int l)
+{
+ struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+ int rc;
+ u8 access;
+
+ rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
+ if (rc < 0)
+ return false;
+
+ if ((access & (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) == TPM_ACCESS_VALID)
+ return true;
+
+ return false;
+}
+
static int release_locality(struct tpm_chip *chip, int l)
{
struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+ unsigned long stop, timeout;
+ long rc;
tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
+ stop = jiffies + chip->timeout_a;
+
+ if (chip->flags & TPM_CHIP_FLAG_IRQ) {
+again:
+ timeout = stop - jiffies;
+ if ((long)timeout <= 0)
+ return -1;
+
+ rc = wait_event_interruptible_timeout(priv->int_queue,
+ (locality_inactive(chip, l)),
+ timeout);
+
+ if (rc > 0)
+ return rc;
+
+ if (rc == -ERESTARTSYS && freezing(current)) {
+ clear_thread_flag(TIF_SIGPENDING);
+ goto again;
+ }
+ } else {
+ do {
+ if (locality_inactive(chip, l))
+ return 0;
+ tpm_msleep(TPM_TIMEOUT);
+ } while (time_before(jiffies, stop));
+ }
return 0;
}
